The shape of things to come

LONDON, England (CNN) -- A futuristic new jet hopes to be the biggest revolution in commercial aircraft design in fifty years.

With a radical new shape, its designers believe it will use 25 percent less fuel that today's planes and be no louder than a car driving down your street.

The research team from the Cambridge-MIT Institute, a collaboration between the two universities and backed by the British government, have spent the last seven years working on a "silent" jet, focussing on noise reduction as the primary design point.

The result is a design unlike the cylindrical fuselage of today's passenger aircraft that it is hoped will be 25 decibels quieter. Resembling a single flying wing, the jet, called the SAX-40, incorporates a "blended-wing" design that smoothly blends the conventional wings of a plane into a wide tailless body.

Instead of wing-mounted engines, the SAX-40 has been designed with the air in-takes embedded into the top of the plane, shielding people on the ground from any engine noise.

The engines themselves would be mounted deep within the in-take ducts and heavily insulated. Another noise-countering feature is the incorporation of a trailing wing edge - long, thin protrusions from the back of the wing - that make the transition between turbulent and non-turbulent air much smoother.

These features should ensure a quieter ride for passengers, and those on the ground, but there are further innovations that would please people living under airport flight paths.

On slower approaches to airports, the airframe of a plane makes as much noise as the engine -- most of it coming from the flaps and lowered undercarriage. The SAX-40 design has eliminated flaps and simplified the undercarriage.

Instead the plane will have a drooped leading edge that will create extra lift, an innovation that Airbus have incorporated in its A380 superjumbo.

With the predicted tripling of air passengers in the next 30 years there is a strong case to be made for quieter jets, as airports will not be able to increase capacity unless they respect their surrounding communities and local noise pollution levels.

The silent jet also has the benefit of being more energy efficient than today's aircraft. The plane's exhausts have also been designed to change their size to generate different amounts of thrust and maximize the engines' performance.

Predictions by the team led by Professor Ann Dowling of Cambridge University estimate that the SAX-40 would fly 149-passenger miles on one gallon of fuel, compared to 120 miles for a Boeing 777, giving it better fuel-efficiency per person per mile than a Toyota Prius car.

"This collaboration has stretched our imagination and generated some ideas that we will be able to study for potential future use," said Jim Morris vice president of Engineering and Manufacturing for Boeing at the project's much hyped unveiling.

Many of the SAX-40 design features are present in Boeing's latest project the X-48B, another blended wing design that the company is developing.

It is more likely that aircraft manufactures will pick elements of the design and adapt them before we see a fully-working SAX-40 in our skies, even though it has support from the aviation industry including companies such as Rolls Royce, British Airways, and Boeing.

As much as the SAX-40 has been touted by its designers are the future shape of aviation, there are huge technical difficulties to be overcome.

Cost-effectiveness issues for airlines and manufacturers would also have to be resolved.

"The reason planes look the way they do today is that they are fundamentally very efficient architecture," says Amy Buhrig, director of Technology for Boeing Commercial Airplanes who has led the team developing the Boeing 787.

"The next plane after the 787 will take composite material technology another leap further, making planes even lighter and stronger," said Buhrig.

Smaller and quieter engines and a lighter airframe are elements of the 787 Dreamliner that Boeing hope will attract airlines and provide the first wave of more economical and quieter jets.

For other experts, the real revolution in aviation will be seen on the inside.

"There have been huge developments in the way to control the plane, from following and direct the flight path with computers, integrated avionics and more electrical systems replacing step-by-step the hydraulics," Philippe Jarry, Airbus' senior vice-president for Product Planning told CNN.

"There are still some good years for the current configuration of planes before new composite materials and manufacturing processes will allow us to make the blended wing body type of aircraft."

While there may be a compelling economical and environmental case behind the design there is one more factor besides the conservative nature of the airline industry that might keep the SAX-40 project grounded.

With fewer windows and a greater distance from the plane's center many critics believe passengers would be more prone to airsickness -- not a pleasant ambient noise to hear over quieter engines.